Safety inner tube for pneumatic tires



Nov. 2, 948. B, CAR N 1 2,452,902

SAFETY INNER TUBE FOR PNEUMATIC TIRES Filed Dec. 7, 1945 Patented Nov. 2, 1948 2,452,902 "SAFETY INNER TUBE jFoR estimate TIRES,

Bernard Carlin. Orange, Tern, ass'ignor or fforty- ;nine one hundredths to W. 0.;Haizlip and'Eichr ar d B. flammaok, both of Nederland, Tern, and .Joe E ner, and 'Lester De Cordova, both of Beaumont, Tex.

Substituted for applicaticn S'rial No. 293,599, September 6, 1939., Thisapplic'atio'n December 7,1945, Serial-No. 633,414

f3 Claims. (oust-242) "This invention relates tb'sarty innertubes for pneumatic tires used "(in "automotive vehicle's, airplanes 'an'a the like and, among other objects, a ms 'to provide an improved pneumatic inner tube havinga plurality of compartments or chambers and Valves so designed and arranged that, when one chamber is punctured or blows "out, the "other 'chainber or chambers will retain the'airin'them for'sufficient time'to permit a driver'tos'top safely andthe'v'alves between the deflated chamber and inflated "chamber or chambers beoperated automatically'by the deformed or flat walljof the punctured chamber as the tire "rolls on the "groundQnojt "only to deflate the inflated chambers gradually, "but also to give the driver a signal that the tire "requires attention. Another object is to "provide jan'inn'er tube having two or more chambers in which an inner chamber may be "inflated to "a higher pressure than the outer chamber, Still another aim is to provide a safety inner tube of this type which will positively prevent a tire casing from becomingfdis'en'gag'ed from the rim after a puncture or 'blo w out occurs. The mainidea is to provide for maximum safety of passengers using such inner tubes on high speed vehicles "and "to avoid disastrous wrecks caused by ordinary blow-outs and punctures.

Other aims and advantages of the invention will appear *in the specification, when considered in connection with the accompanying drawings,

wherein;

Fig. 1 is a vertical sectional "view of an inner tube embodying a form of the invention a'nd Fig. 2 is an enlarged fragmentary sectional n w taken on the line 2-2 or Fig. 1.

This application is a substitute application to replaee *in'yprior application, Ser. No. 293,599, filedsept. 6, 1939.

Referring particularly to the drawings, in Fig. 1, a main tube 2 1 is shown as being divided into separated compartments or chambers by flexible inelastic webs 22 and 23. In this example, the two web's 22 and 23 are arc-shaped and divide the tube into three "compartments or chambers 24, 25 and 25, the 'two'char'nbers 25 and '26 bein generally elliptical and on "opposite sides of the tube, and the webs 22 and 23 are spaced from each other on the inside, so that the chamber 24 extends vertically across the tube and has an inner portion 21 next to the rim through which the tube is inflated. In this form of the invention, the tube 2|, where it forms the outer walls of the chambers 25, 26 and the portion 21 of chamber 24, is composed of rubberized cord .2 fabric or reinforced rubber which is relatively inelastic and flexible; while the outside wall 28 of the chamber 24 is made of elastic rubber so that it can be vulcanized, and easily repaired. Also this elastic portion permits the inner tube to expand'and-contact the inside wall of the tire casing. I

The two arcuate webs 22 and 23,Which form thechambers 25 and 26, are shown as being reinforced and are connected by separate rubberized fabric web sections or ribs 29 and 38] having openings or perforations permitting the inner portion 21 of chamber 24 to communicate with the'outside of this chamber.

In this form of the invention the inflating air is admitted to the portion 2? of chamber 24 through an ordinary valve stem 3! and passes into the chamber 24 as has just been explained.

From the chamber 24, the air is permitted to pass into the chambers 25 and 26 through double flap valves 32, each composed of semi-flexible strips of rubberized fabric vulcanized at one end to the opposite faces of the webs 22 and 231. The

free ends of the opposite flaps are shown as being connected bya stem or-spacer 33 passing through a port 34. These double-acting valves are prefe'n ably arranged, as shown in Fig. 1, with the free ends ofthe lower flaps adjacent to the inside Wall of the section 28 of the main tube. The arrangement of these valves is such that both flaps will be held out of contact with the ports through the webs, while the tube is being inflated. They are preferably slightly biased to close the ports inside the chambers 25 and 25 so that the the two flap valves 32 will close because of the greater pressure in the chambers 25 and 25.

The arrangement of the two valves is such that when the tube is punctured through the section 28, the wall will flatten out on the ground or pavement and will engage the lower end portions of the flaps in the chamber 24, thus opening the flap valves upon each revolution of the wheel or tireand imparting an audible signal as well as a slight jar or shock to the vehicle. Thus, the driver or pilot may hear the air escaping upon each revolution of the wheel. Also the slight jar or shock upon each revolution of the wheel will be perceptible to the driver both through the steering wheel and the body of the vehicle. It will be noted that when the tube is punctured or blown out through the chamber 24, both of the side chambers 25 and 26 will remain inflated and will retain the casing in engagement with the tire rim. Also, these inflated compartments will keep the tire sufficiently inflated to enable it to be used for a mile or more so that a driver will have ample time to slow down the vehicle without danger of turning over. The connecting ribs between the webs will prevent chambers from being displaced. In the event that one of the side compartments or chambers 25 and 26 is deflated by a blow-out, the driver will be warned only by the noise. The side walls of the tire are not often punctured. When this happens, the flaps of the valves 32 will change their posi tion to prevent air from escaping from the-chamber 24 to and through the ruptured chamber. The inflated chamber 24 will support the tire and hold the casing on the rim even when both side chambers blow out.

If one of the side chambers has been blown out and it is desired to repair the tire, the chamber 24 may be deflated through the valve stem 3| and the air may then be exhausted from the other side chamber by pressing upon and deforming the casing to open the flap valve.

From the foregoing description, it will be seen that the improved safety tube is contrived to promote maximum safety of passengers and will positively prevent disastrous wrecks or accidents usually caused by ordinary punctures or blowouts. Such tubes do not have to be punctured to permit removal of the tire casing and they are capable of being repaired by vulcanization. They can be made and sold at a reasonable price and it is contemplated that they will be widely adopted in the promotion of safety.

Obviously, the present invention is not restricted to the particular embodiment thereof herein shown and described. Moreover, it is not indispensable that all the features of the invention be used conjointly, since they may be employed advantageously in various combinations and sub-combinations.

What is claimed is:

1. A safety pneumatic inner tube of the class described comprising a main tube; a pair of ar-cuate webs within the tube each extending from one side of the rim portion to a side of the tread portion and dividing the tube into three chambers, one in each side and one extending through the middle from the rim portion to the tread portion; reinforcing rubberized ribs connecting said webs together near the center of the tube; an inflating valve connected to the middle chamber; double acting check valves on opposite sides of the walls between the middle chamber and the side chambers connected to permit inflation of the side chambers through the middle chamber butpreventing escape of air from the middle chamber through a side chamber after either side chamber blows out.

2. A safety pneumatic inner tube of the class described comprising a main tube; a pair of arcuate webs within the tube =each extending from one side of the rim portion to a side of the tread portion and dividing the tube into three chambers, one in each side and one extending through the middle from the rim portion to the :tread portion; reinforcing ribs connecting said webs near the center of the tube; said ribs, said webs and the side walls of the tube forming the side chambers being composed of rubberized cord fabric; an inflating valve connected to the middle chamber; double acting check valves on opposite sides of the walls between the middle chamber and the side chambers arranged to permit infl tion of the side chambers through the midd e chamber but preventing escape of air from the middle chamber through a side chamber after either side chamber blows out.

3. A safety pneumatic inner tube of the class described comprising a main tube; :a pair of arcuate webs within the tube each extending from one side of the rim portion to a side of the :tread portion and dividing the tube into three chambers, one in each side and one extending through the middle from the rim portionto the tread portion; an inflating valve connected to the middle chamber; double acting check valves between the middle chamber and the side chambers permitting inflation of the side chambers through the middle chamber but preventing escape of air from the middle chamber through ,a side chamber after either side chamber blows out, said double acting check valves being composed of-a pair of flaps in the form of rubberized cord fabric vulcanized on opposite sides of each web near the tread with a spacer arm or finger extending through the valve opening, and the flaps on the lower side of each web adapted to be engaged. by the deformed or flattened tread portion of the tube when the middle chamber is punctured or blown out and as the tire rot-ates on the ground or pavement to deflate the side chambers gradually by escaping puffs of air to give-a signal to a driver or pilot.

BERNARD CARLIN.

REFERENCES (JITED The following references are of record in the file of this patent:

UNITED STATES PATENTS" Number Name Date 627,972 Brady July 4, 1899 1,325,233 Cooper Dec. 16, 1916 1,462,942 Rogers July 24, 1923 1,952,221 Ronneberg Mar. 27, 1934 1,962,143 Ford June 12, 1934 2,169,041 Gammeter Aug. 8, 1939 FOREIGN PATENTS Number Country Date H 29 267 Netherlands 1933 222,478 Great Britain 1924 578,007 France 1924 599,072 France 1926 

